Washing or cleaning agents and cosmetic agents usually contain scents, which impart a pleasant odor to the agents. At the same time, the scents usually mask the odor of other ingredients so that a pleasant odor impression is obtained by the consumer.
In the sector of washing agents in particular, scents are important constituents of the composition, since the laundry should have a pleasant and also a fresh scent, both in the wet and in the dry state. With the use of scents, one is faced with the fundamental problem that these are more or less volatile compounds, but yet a long-lasting scent effect is desired. In particular in the case of those scents that represent the fresh and light notes of the perfume and, as a result of their high vapor pressure, evaporate particularly rapidly, the desired long life of the scent impression is extremely difficult to achieve.
A delayed release of scent can take place e.g. by a carrier-bound use of scents. A carrier-bound precursor of a scent is also referred to as a “pro-fragrance” or scent storage substance. In connection with this, the international patent application WO 2007/087977 discloses the use of 1-aza-3,7-dioxabicyclo[3.3.0]octane compounds as pro-fragrances for the delayed release of scent aldehydes and scent ketones by hydrolysis. An alternative possibility for delayed release of scents involves the use of so-called photoactivatable substances as pro-fragrances. The action of sunlight or of another electromagnetic radiation source of a specific wavelength induces breakage of a covalent bond in the pro-fragrance molecule, thereby releasing a scent.
WO 2011/101180 discloses the use of specific ketones as photo-activatable substances that release an active substance in the presence of light in a photochemical fragmentation. The said active substance possesses e.g. a scent-imparting activity, which is at first delayed by the photochemically induced breakdown, and released over a longer period of time on a specific surface.
The object of the present invention is to provide photoactivatable substances as pro-fragrances, which permit the delayed release of scent ketones and scent esters and which attach particularly well to surfaces, in particular to textile surfaces.
Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.